Boron carbide (B4C) materials are great of interest as engineering ceramics for armor, wear resistant structural components, and as abrasives. Most applications of boron carbide materials require a high density which is close to the theoretical density (TD). Boron carbide materials generally have been made using either hot pressing techniques (i.e., sintering under high pressure) or pressureless sintering (i.e., sintering without applying pressure).
Typically, hot pressing processes are limited to relatively small and geometrically simple articles. Also, hot pressing processes generally are energy intensive and require additional molding materials.
Attempts have been made to replace hot pressing by pressureless sintering, to manufacture articles from a composite material including boron carbide. Pressureless sintering is advantageous compared to hot pressing with respect to process costs and ability of processing in a continuous mode and/or a scale-up to commercial production. Generally, it has been a challenge for conventional pressureless-sintering processes to obtain sintering densities of more than about 95% TD. Thus, there is a need for developing an improved pressureless-sintering process to manufacture high density boron carbide materials or products.